Will Synchronised be the first horse since 1934 to win the Grand National and Cheltenham Gold Cup in one season? And if you're following the race at home, why not print out our sweepstake kit?
The steeplechase, which has been run at Aintree since 1839, has seen modifications since last year, when two horses died. Washing-off and cooling areas have been provided for the horses, and three of the fences have been modified.
The nine-year-old Synchronised, with the burden of carrying the top weight of 11st 10lb after the 40-strong field was declared, is 6-1 favourite to win a landmark double for owner JP McManus, trainer Jonjo O'Neill, and champion jockey Tony McCoy.
Last year's winner, Ballabriggs, trained by Donald McCain, is 12-1. If he wins, he will become the first horse since Red Rum to land back-to-back Grand National victories.
On His Own, Ruby Walsh's mount, heads Willie Mullins' team. Walsh's jockey sister, Katie, will be aboard Seabass. Nina Carberry, who is also bidding to become the first female National winner, will be aboard Organisedconfusion.
The other major contenders include Giles Cross, West End Rocker, Junior, Cappa Bleu, Chicago Grey and Killyglen.
Welsh National winner Le Beau Bai, a top-priced 40-1, has been withdrawn, as also has Always Waining. It means Hello Bud and Neptune Equester can join the world's greatest steeplechase.
More than £300m is expected to be bet on the Grand National. With the arrival of rain this week, one of the best backed horses over the past five days has been West End Rocker, whose price has tumbled to 11-1 from 16-1 on Monday.
"It'll be a shocker if West End Rocker wins. There's more rain forecast for Liverpool before the big race and every drop will enhance his chances," said Ladbrokes' spokesman David Williams.
19 March 2012